Medical device control system

ABSTRACT

A medical device control system improves an inducing stability and operability of a medical device having its direction controlled with magnetism, which is used for the inspection or treatment in a subject&#39;s body. The control system is formed of a medical device including an insertion member inserted into the subject&#39;s body, and a magnetic field response portion disposed within the insertion member for generating torque in response to the magnetic field applied from outside the subject&#39;s body, a direction detection unit that detects an insertion direction of the insertion member, a user interface through which the information with respect to the control of the insertion direction is input and output, a magnetic field generation portion that generates a magnetic field that directs the insertion member to a control direction, and a user interface control unit that controls the user interface based on a discordance between the control direction and the insertion direction.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation Application of U.S. Ser. No.11/630,730 filed on Dec. 21, 2006, which is a national stage applicationunder PCT/JP2006/317669 filed on Sep. 6, 2006, which claims the benefitof priority to JP 2005-085939, filed on Mar. 24, 2005, the contents ofeach of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a medical device control system.

2. Description of Related Art

Recently, there has been research and development of swallowable capsulemedical devices, as represented by capsule endoscopes and the like, thatare swallowed by a subject to enter the subject's body, where theytraverse a passage in the body cavity to capture images of a target siteinside the passage in the body cavity. The capsule endoscopes describedabove have a configuration in which an imaging device that can performthe medical procedure described above, for example, a CCD (ChargeCoupled Device) that can acquire images or the like, is provided andperform image acquisition at the target site inside the passage in thebody cavity.

The aforementioned capsule medical device may only be moved through thedigestive tract by action of peristalsis but not controlled with respectto its position and direction. Location of the capsule medical devicewithin the passage in the body cavity has been required to induce thecapsule medical device so as to be allowed to perform easy diagnosis.

The technique for locating the medical device that has been induced tothe site (within the passage in the body cavity) that cannot be visuallyidentified so as to be further induced to the target site has beendisclosed in Japanese Unexamined Patent Application, publication No.2004-25174 (hereinafter referred to as Patent Document 1).

The above-described technique is required not only for the capsulemedical device but also for the medical device equipped with the probethat is induced into the passage in the cavity of the subject's body.The technique for locating the medical device that has been induced tothe site (within the passage in the body cavity) that cannot be visuallyidentified so as to be further guided to the target site has also beendisclosed in PCT International Publication No. WO00/07641 (Pamphlet)(hereinafter referred to as Patent Document 2).

BRIEF SUMMARY OF THE INVENTION

The disclosure of Patent Document 1 relates to the system forcontrolling the medical device inserted into the body cavity with themagnetic field. According to the disclosure, the magnetic field to begenerated for controlling the medical device is determined based on thedirection information obtained by the device for detecting the directionof the medical device.

Patent Document 1 discloses only the concept with respect todetermination of the magnetic field generated for the medical devicebased on the direction information detected by the device for detectingthe direction of the medical device without proposing the specificprocess for such determination. Likewise Patent Document 2, it tends todeteriorate controllability (inducing stability, operability) of themedical device when a large discordance occurs between direction of themedical device and the magnetic field direction.

Patent Document 2 discloses the technique that allows the operator tocommand and determine the direction for generating the magnetic fieldwhile confirming the position and direction of the catheter using thefluoroscope.

Since the information on the position and direction of the catheter isacquired as the image information such that the operator reads thedisplayed image information to command and determine the direction forgenerating the magnetic field, the position and direction informationcannot be constantly monitored.

This may fail to prevent the large discordance in the direction betweenthe catheter and the magnetic field. In the case where the largediscordance in the direction occurs between the catheter and magneticfield, the controllability (inducing stability and operability) of thecatheter may be deteriorated.

Japanese Unexamined Patent Application, Publication No. 2003-111720relates to the control such that the force acting on the intra-bodyrobot becomes proportional to the force acting on the input device. Theresultant system becomes complicated because of the requirement forcalculating the force acting on the intra-body robot.

It is an object of the present invention to provide a medical devicecontrol system that improves inducing stability and operability withrespect to the medical device used for performing the inspection ortreatment of the subject's body under the direction control with themagnetic field.

The present invention provide following means for the purpose ofachieving the aforementioned object.

A first aspect of the present invention provides a medical devicecontrol system formed of a medical device including an insertion memberinserted into a subject's body and a magnetic field response portionthat generates torque in response to a magnetic field applied fromoutside the subject's body, a direction detection unit that detects aninsertion direction of the insertion member, a user interface throughwhich information with respect to a control of the insertion directionis input and output, a magnetic field generation portion that acts onthe magnetic field response portion to generate the magnetic field thatdirects the insertion member to a control direction, and a userinterface control unit that controls the user interface based on adiscordance between the control direction and the insertion direction.

According to the first aspect of the invention, the user interfacecontrol unit controls the user interface based on the discordance. Thediscordance, thus, may be transferred to the outside via the userinterface. For example, it is possible to feedback the discordance tothe operator who inputs the control direction to the user interface,thus improving the inducing stability and operability of the medicaldevice.

In the first aspect of the present invention, preferably, the userinterface is provided with an operation unit through which an operatorcommands the insertion direction, and the operation unit is providedwith a discordance information transmission portion controlled by theuser interface control unit for transmitting the discordance to theoperator.

The discordance may be transferred to the operator from the discordanceinformation transfer unit provided in the operation unit. Thediscordance may be easily feedbacked to the operator, improving theoperability of the insertion member.

Preferably, the discordance information transfer unit is formed as anoscillating body.

The information based on the discordance may be transferred to theoutside as the oscillation generated by the oscillating unit. Forexample, the frequency of the generated oscillation may be increased asthe discordance becomes large. Meanwhile, the frequency of theoscillation may be decreased as the discordance becomes small so as totransfer the information based on the discordance.

In the aforementioned structure, preferably, the operation unit isprovided with a movable body through which the control direction isinput, and the discordance information transmission portion is areaction force generation portion that generates a force in a directionopposite a movement of the movable body.

When the control direction is input by moving the movable body, thereaction force generating unit generates the force (reaction force)acting in the direction opposite the moving direction of the movablebody so as to notify the operator of the discordance. For example, whenthe discordance becomes large, the reaction force with respect to themovement of the movable body is increased. Meanwhile, when thediscordance becomes small, the reaction force is decreased. This makesit possible to notify the operator of the level of the discordance. Theoperability of the movable body may be improved since the operator isallowed to perform the realistic operation.

In the aforementioned structure, preferably, the operation unit isprovided with a movable body through which the control direction isinput, and the discordance information transmission portion is a loadgenerating portion that generates a load to a movement of the movablebody.

When the control direction is input by moving the movable body, the loadgeneration unit generates the load to the movement of the movable bodyso as to notify the operator of the discordance. For example, when thediscordance becomes large, the load to the movement of the movable bodyis increased. Meanwhile, when the discordance becomes small, the load isdecreased. This makes it possible to notify the operator of the level ofthe discordance. The operability of the movable body may be improvedsince the operator is allowed to perform the realistic operation.

The operation unit may be formed more easily compared to the process forgenerating the force in the direction opposite the movement of themovable body.

According to the first aspect of the present invention, preferably, theuser interface is provided with a display unit that displays theinsertion direction and the discordance, and the display unit iscontrolled by the user interface control unit.

The display unit provided for the user interface may be controlled bythe user interface control unit. As the insertion direction and thediscordance are displayed on the display unit, the operator may benotified of the discordance. The discordance may be easily feedbacked tothe operator who inputs the control direction, thus improving theoperability of the insertion member.

According to the first aspect of the invention, the user interface isprovided with a display unit that displays the insertion direction andthe discordance, and the display unit is controlled by the userinterface control unit. Further, the display unit displays informationof the insertion direction and information of the control directionsuperimposed thereon.

The superimposed image of the insertion direction and the controldirection may be displayed on the display unit. This allows the operatorwho inputs the control direction to identify the control stateintuitively, thus improving the operability of the insertion member.

According to the first aspect of the present invention, the userinterface is provided with a display unit that displays the insertiondirection and the discordance, and the display unit is controlled by theuser interface control unit. Preferably, the display unit displays thediscordance between the insertion direction and the control direction.

The discordance of the control direction from the inserting direction isdisplayed such that the operator who inputs the control direction may beeasily notified of the control state.

For example, the discordance amount may be displayed as the numericaldata, length, vector and the like. Alternatively, the alarm signal maybe displayed when the discordance exceeds the predetermined discordancevalue, or when a predetermined time period elapses in the state wherethe discordance is kept in excess of the predetermined discordance.

According to the first aspect of the invention, preferably, a magneticfield control unit that controls the magnetic field generation portionis provided, and the magnetic field control unit controls the magneticfield generation portion such that a value of the discordance is equalto or smaller than a predetermined value. More preferably, a magneticfield control unit that controls the magnetic field generation portionis provided, and the magnetic field control portion controls themagnetic field generation portion such that a value of the discordanceis equal to or smaller than a predetermined value, and further themagnetic field control unit includes a predetermined value changeportion that changes the predetermined value with a finite value.

The magnetic field generation portion is controlled by the magneticfield control unit for controlling the magnetic field direction suchthat the discordance does not exceed the predetermined value. This mayprevent deterioration in the operability of the insertion member due toexcessive increase in the discordance.

The predetermined value change portion changes the predetermined valueto a finite value. This makes it possible to prevent the discordancefrom exceeding the range that can be controlled by the medical unitcontrol system. Further, the predetermined value may be defined inaccordance with the medical unit control system so as to reliablyprevent deterioration in the operability of the insertion member.

A second aspect of the invention provides a medical device controlsystem formed of a medical device including an insertion member insertedinto a subject's body, having its direction controlled by magnetism, anda magnetic field response portion disposed within the insertion memberfor generating torque in response to a magnetic field applied fromoutside the subject's body, a direction detection unit that detects aninsertion direction of the insertion member, a user interface throughwhich a control direction for the insertion direction is input by anoperator, a magnetic field generation portion that generates a magneticfield that acts on the magnetic field response portion, and a magneticfield control unit that controls the magnetic field generation portionbased on a discordance between the insertion direction and the controldirection.

In the second aspect of the invention, the magnetic field may becontrolled by the magnetic field control unit based on the discordance,thus preventing deterioration in the operability of the insertionmember. In the case where the magnetic field generated by the magneticfield generation portion is not suitable for inducing the insertionmember toward the control direction, and the discordance becomes large,the magnetic field may be changed to the one suitable for inducing theinsertion member. This makes it possible to prevent increase in thediscordance.

According to the second aspect of the invention, preferably, themagnetic field control unit includes a magnetic field pattern storageportion that stores a plurality of magnetic field generation patterns,and a magnetic field pattern change portion that selects a magneticfield pattern from the plurality of magnetic field generation patternsso as to be generated based on the discordance, and changes the magneticfield pattern generated by the magnetic field generation portion to theselected magnetic field pattern.

Among the plurality of magnetic field patterns stored in the magneticfield pattern storage unit, the one suitable for controlling theoperation unit is selected by the magnetic field pattern change unitbased on the discordance such that the magnetic field pattern is changedto the selected one that has been generated by the magnetic fieldgeneration portion. In the case where the magnetic field pattern is notsuitable for inducing the insertion member toward the control direction,and the discordance becomes large, the magnetic field pattern suitablefor inducing the insertion member is selected to be changed. This makesit possible to prevent increase in the discordance such that thedeterioration in the operability of the insertion member may be furtherprevented.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially perpendicular to the insertion direction, andone of the plurality of magnetic field patterns stored in the magneticfield pattern storage portion is a revolving magnetic field thatrevolves on a plane substantially perpendicular to the controldirection.

The magnetic field response portion is formed as a magnet that exhibitsmagnetization direction substantially perpendicular to the insertiondirection. The revolving magnetic field is activated to rotate themagnet such that the insertion member is rotated around the rotatingaxis along the direction for inserting the insertion member.

The insertion member is rotatably driven to control the insertion memberreliably compared to the magnetic field generated by combining therevolving magnetic field and the oscillating magnetic field, or therevolving magnetic field.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially perpendicular to the insertion direction, andone of the plurality of magnetic field patterns stored in the magneticfield pattern storage portion is a magnetic field formed by combining arevolving magnetic field that revolves on a plane substantiallyperpendicular to the control direction and an oscillating magnetic fieldthat oscillates substantially in parallel to the control direction.

The magnetic response portion is formed as the magnet that exhibits themagnetization direction substantially perpendicular to the insertionmember. The magnetic field pattern formed by combining the revolvingmagnetic field and the oscillating magnetic field is activated on themagnetic field response portion to control the revolving plane in therevolving magnetic field toward the predetermined direction. This makesit possible to swing the insertion member around the axis along theinserting direction while revolving its leading end.

In the case where the insertion member is inserted into the narrowedpassage of the body cavity, the insertion member is swingably revolvedwhile widening the passage of the body cavity. This makes it possible toallow penetration of the insertion member into the widened passage ofthe body cavity.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially perpendicular to the insertion direction. One ofthe plurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is a fluctuating magnetic field having itsdirection fluctuated on a plane substantially perpendicular to thecontrol direction. An angle formed by an intersection line of a planesubstantially perpendicular to the control direction with a plane thatcontains the insertion direction and the control direction, and themagnetic field direction of the fluctuating magnetic field varies withina predetermined range.

The magnetic field response portion is formed as the magnet thatexhibits the magnetization direction substantially perpendicular to theinsertion member. As the fluctuation magnetic field having the magneticfield direction fluctuating within the predetermined range is activatedon the magnetic field response portion, the torque constantly acts todirect the insertion member toward the predetermined range.

For example, the predetermined range may be made accorded with thecontrol direction of the insertion member so as to constantly generatethe torque for directing the insertion member toward the controldirection, thus efficiently changing the direction of the insertionmember.

In the aforementioned structure, the magnetic field response portion isa magnet or an electromagnet that exhibits a magnetization directionsubstantially perpendicular to the insertion direction. One of theplurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is a fluctuating magnetic field having itsdirection fluctuated on a plane substantially perpendicular to thecontrol direction. An angle formed by an intersection line of a planesubstantially perpendicular to the control direction with a plane thatcontains the insertion direction and the control direction, and themagnetic field direction of the fluctuating magnetic field varies withina predetermined range. Preferably, an intensity of the fluctuatingmagnetic field is kept constant, and an angle formed by the direction ofthe fluctuating magnetic field, and the intersection line variescontinuously within a predetermined range.

In the aforementioned structure, as the angle defined by the magneticfield direction of the fluctuation magnetic field and the intersectioncontinuously changes within the predetermined range, the position of theinsertion member may be reliably controlled compared to the case wheresuch angle changes intermittently.

In the aforementioned structure, preferably, the magnetic field patternchange portion generates a magnetic field pattern having the magneticfield revolved on a plane substantially perpendicular to the insertiondirection subsequent to the magnetic field pattern currently generatedby the magnetic field generation portion, and further generates a nextmagnetic field pattern thereafter.

The magnetic field pattern that has been currently generated may bechanged to the different one by generating the magnetic field patternhaving the magnetic field revolved on the plane substantiallyperpendicular to the insertion direction. Thereafter, the differentmagnetic field pattern is generated so as to keep the reliable controlfor the insertion member.

The magnetic field pattern is changed via the magnetic field patternthat revolves and is controllable with respect to the insertingdirection reliably.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially perpendicular to the insertion direction. One ofthe plurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is a fluctuating magnetic field having itsdirection fluctuated on a plane substantially perpendicular to thecontrol direction. Preferably, the insertion member is substantiallycylindrical, and provided with the magnetic field response portionrotatably around a center axis of the insertion member.

The magnetic field response portion is rotatably disposed with respectto the insertion member. For example, even if the magnetic fieldresponse portion is driven to rotate, the insertion member is not drivento rotate. In the case where the direction of the magnetic fieldresponse portion is changed, the direction of the insertion member maybe changed accordingly.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially perpendicular to the insertion direction. One ofthe plurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is a revolving magnetic field that revolves on aplane substantially perpendicular to the control direction. Preferably,the magnetic field response portion is fixed to the insertion member.

The magnetic field response portion is fixed to the insertion member. Asthe magnetic field response portion is driven to rotate, the insertionmember is also rotated accordingly.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially in parallel to the insertion direction. One ofthe plurality of the magnetic field patterns stored in the magneticpattern storage portion is an oscillating magnetic field that oscillatesaround the control direction, and an angle formed by the oscillatingmagnetic field and the control direction is within a predeterminedrange.

The magnetic field response portion is formed as a magnet directedtoward magnetization substantially parallel to the insertion direction.The oscillating magnetic field where the magnetic field directionfluctuates in the predetermined range is caused to act on theaforementioned magnet such that the insertion member oscillates withrespect to the control direction.

For example, the oscillating magnetic field is caused to act forswinging oscillation with respect to the control direction for thepurpose of swingably oscillating the insertion member. This makes itpossible to widen the nearly closed passage of the body cavity throughthe swingable oscillation of the insertion member, and to allow theinsertion member to penetrate through the widened passage of the bodycavity.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially in parallel to the insertion direction. One ofthe plurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is the magnetic field formed by combining themagnetic field substantially in parallel to the insertion direction anda revolving magnetic field that revolves on a plane substantiallyperpendicular to the insertion direction.

The magnetic field response portion is formed as a magnet that exhibitsthe magnetization direction substantially perpendicular to the insertiondirection. The magnetic field pattern formed by combining thesubstantially parallel magnetic field and the revolving magnetic fieldis caused to act for the purpose of swingably rotating the insertionmember with respect to the inserting direction.

In the aforementioned structure, preferably, the magnetic field responseportion is a magnet or an electromagnet that exhibits a magnetizationdirection substantially in parallel to the insertion direction. One ofthe plurality of magnetic field patterns stored in the magnetic fieldpattern storage portion is a fluctuating magnetic field having itsdirection fluctuated on a plane that contains the insertion directionand the control direction.

The magnetic field response portion is formed as a magnet that exhibitsthe magnetization direction substantially perpendicular to the insertiondirection. The magnetic pattern having the magnetic field directionchanged on the aforementioned plane is caused to act for the purpose ofeasily directing the insertion member toward the control direction.

In the aforementioned structure, the magnetic field response portion isa magnet or an electromagnet that exhibits a magnetization directionsubstantially in parallel to the insertion direction. One of theplurality of the magnetic field patterns stored in the magnetic patternstorage portion is an oscillating magnetic field that oscillates aroundthe control direction. An angle formed by the oscillating magnetic fieldand the control direction is within a predetermined range. Preferably,the magnetic field response portion is a magnet or an electromagnet thatexhibits a magnetization direction substantially in parallel to theinsertion direction. One of the plurality of magnetic field patternsstored in the magnetic field pattern storage portion is a fluctuatingmagnetic field having its direction fluctuated on a plane perpendicularto a plane that contains the insertion direction and the controldirection.

The magnetic field response portion is formed as a magnet that exhibitsthe magnetization direction substantially perpendicular to the insertiondirection. The magnetic field pattern having the magnetic fielddirection changed on the substantially perpendicular plane is caused toact for the purpose of easily directing the insertion member toward thecontrol direction.

In the aforementioned structure, preferably, the magnetic field patternchange portion generates a magnetic field pattern having the magneticfield substantially in parallel to the insertion direction subsequent tothe magnetic field pattern currently generated by the magnetic fieldgeneration portion, and further generates a next magnetic field patternthereafter.

The magnetic field pattern currently generated is changed to thedifferent one by generating the magnetic field pattern substantially inparallel to the direction of the insertion member. Thereafter, thedifferent magnetic field pattern is generated to keep the stabilizedoperation of the insertion member.

The control stability of the insertion member may be kept by changingthe magnetic field pattern via the one substantially in parallel to thedirection of the insertion member, thus stabilizing the operation of theinsertion member.

According to the second aspect of the present invention, preferably, themagnetic field control unit is provided with a magnetic field intensitychange portion that changes an intensity of the magnetic field based onthe discordance.

The force acting on the insertion member to change the direction may beincreased by intensifying the magnetic field. Accordingly, in the casewhere the discordance becomes large, the magnetic field is increased toenable the control in the state more reliable than the case thediscordance is further increased.

A third aspect of the present invention provides a medical devicecontrol system formed of a medical device including an insertion memberinserted into a subject's body, and a magnetic field response portiondisposed within the insertion member to generate torque in response to amagnetic field applied from outside the subject's body, a directiondetection unit that detects an insertion direction of the insertionmember, a magnetic field generation portion that acts on the magneticfield response portion to generate a magnetic field for directing theinsertion member to a control direction, and a magnetic field controlunit that controls the magnetic field generation portion such that adiscordance between the insertion direction and the control direction isequal to or smaller than a predetermined value.

According to the third aspect of the invention, the magnetic fieldgeneration portion is controlled by the magnetic field control unit toregulate the magnetic field direction, thus preventing the discordancefrom exceeding the predetermined value. This makes it possible to avoiddeterioration in the operability of the insertion member owing to theexcessive discordance.

For example, even if the discordance between the direction of theinsertion portion and the control direction due to the external forceacting on the insertion member, the discordance may be prevented fromexceeding the predetermined value by controlling the magnetic fielddirection.

According to the third aspect of the present invention, preferably, whenthe discordance exceeds the predetermined value, the magnetic fieldcontrol unit controls the magnetic field generation portion such thatthe control direction substantially accords with the insertiondirection.

When the discordance becomes large to exceed the predetermined value,the magnetic field direction is changed conforming to the direction ofthe insertion member at the time point. In the case where the insertionmember penetrates through the passage of the internal organ, it isallowed to move forward along the wall surface of the internal organwithout requiring the control information acquired through the externalinput.

According to the third aspect of the invention, preferably, the magneticfield control unit is provided with a predetermined value change portionthat changes the predetermined value within an effective range.

The predetermined value change portion is capable of changing thepredetermined value within an effective range.

According to the first to the third aspects of the invention,preferably, the insertion member includes a driving force generationportion that generates a driving force in the insertion direction.

The driving force generating unit allows the driving force to be appliedto the insertion member. Especially in the case where the magnetic fieldcontrol unit controls the magnetic field generation portion such thatthe discordance between the direction for inserting the insertion memberand the control direction thereof becomes equal to or smaller than thepredetermined value, when the control direction is changed by the wallof the internal organ as a result of penetration of the insertion memberthat has been driven, the control direction may be changed to adjust thediscordance to be equal to or smaller than the predetermined value. Theinsertion member is automatically inserted along the wall surface of thepassage in the internal organ.

In the medical device control system according to the invention, thecontrol unit controls the user interface based on the discordance. Thismakes it possible to transmit the information based on the discordanceto outside via the user interface. Accordingly, the information based onthe discordance may be feedbacked to the operator who inputs the controldirection information to the user interface, resulting in such effectsas the improved inducing stability and operability of the medical device(insertion member).

Additionally, the control unit is allowed to induce the insertion memberconforming to the situation for the purpose of controlling the magneticfield generation portion based on the discordance. This makes itpossible to further improve the inducing performance using the simplystructured system.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a schematic view showing a structure of a capsule endoscopecontrol system according to the first aspect of the invention;

FIG. 2 is a schematic view of a system configuration of the capsuleendoscope control system shown in FIG. 1;

FIG. 3 is a control block diagram with respect to the capsule endoscopecontrol system shown in FIG. 1;

FIG. 4 is a view of selection of the magnetic field pattern shown inFIG. 3;

FIG. 5 is a schematic view showing the capsule endoscope and theextracorporeal device shown in FIG. 1;

FIG. 6A is an explanatory view of a display on a display unit shown inFIG. 1;

FIG. 6B is an explanatory view of a display to be shown when thediscordance exceeds a boundary condition (discordance amount andduration);

FIG. 7A is a view showing the concept of the control direction displayedon the display unit shown in FIGS. 6A and 6B;

FIG. 7B is a view showing the state where the control direction isdisplayed on the capture image display;

FIG. 8A is a schematic view of the operation unit;

FIG. 8B is a schematic view of the structure of the direction controllever shown in FIG. 8A;

FIG. 9A is an explanatory view of another structure of the directioncontrol lever shown in FIG. 8B;

FIG. 9B is an explanatory view of another structure of the directioncontrol lever shown in FIG. 8B;

FIG. 10A is an explanatory view showing how the control directioninformation of the capsule endoscope is input through the directioncontrol lever;

FIG. 10B is an explanatory view showing the control direction of thecapsule endoscope based on the control direction information that hasbeen input through the direction control lever;

FIG. 11A is an explanatory view of the revolving magnetic fieldgenerated around the capsule endoscope in the revolving magnetic fieldmode;

FIG. 11B is an explanatory view of the capsule endoscope that rotates inthe revolving magnetic field mode;

FIG. 12 is an explanatory view of the magnetic field generated in thejiggling mode;

FIG. 13 is an explanatory view of the magnetic field generated in themaximum torque mode;

FIG. 14 is an explanatory view of the magnetic field change pattern inthe maximum torque mode;

FIG. 15 is a schematic view showing the automatic insertion mode of thecapsule endoscope;

FIG. 16 is a schematic view showing the automatic insertion mode of thecapsule endoscope;

FIG. 17 is a schematic view showing the automatic insertion mode of thecapsule endoscope;

FIG. 18A is an explanatory view of an exemplary discordance managementcontrol mode;

FIG. 18B is an explanatory view of another exemplary discordancemanagement control mode;

FIG. 19A is an explanatory view of further exemplary discordancemanagement control mode, wherein the axis of abscissas represents theoperation direction information input through the direction controllever;

FIG. 19B is an explanatory view of another exemplary discordancemanagement control mode, wherein the axis of abscissas represents time;

FIG. 20A is a view showing an example of a relationship between thediscordance information and the feedback information to the operationunit;

FIG. 20B is a view showing another example of the relationship betweenthe discordance information and the feedback information to theoperation unit;

FIG. 21 is a view showing further example of the relationship betweenthe discordance information and the feedback information to theoperation unit;

FIG. 22A is an explanatory view showing fluctuation of the torque actingon the capsule endoscope, indicating a positional relationship thatmaximizes the torque;

FIG. 22B is an explanatory view showing fluctuation of the torque actingon the capsule endoscope, indicating the positional relationship thatminimizes the torque;

FIG. 23 is an explanatory view of the fluctuation of the torque in therevolving magnetic field;

FIG. 24 is a schematic view showing another embodiment of the capsuleendoscope shown in FIG. 1;

FIG. 25 is a schematic view showing further embodiment of the capsuleendoscope shown in FIG. 1;

FIGS. 26A, 26B, and 26C are views each showing another embodiment of thecapsule endoscope shown in FIG. 1;

FIGS. 27A and 27B are views each showing an example of the endoscope towhich the structure of the capsule endoscope shown in FIG. 1 is applied;

FIGS. 28A, 28B, and 28C are explanatory views each showing anotherexample of the display unit and operation unit shown in FIGS. 6A, 6B,and 8A and 8B, respectively;

FIG. 29 is a view schematically showing the structure of the probecontrol system according to the second aspect of the invention;

FIG. 30 is an explanatory view of an arrangement of the permanent magnetinstalled in the probe shown in FIG. 29;

FIG. 31 is an explanatory view showing the structure of the capsuleendoscope to which the probe structure shown in FIG. 30 is applied;

FIG. 32 is an explanatory view showing the state where the parallelmagnetic field is generated around the probe;

FIG. 33 is an explanatory view showing the state where the conicalmagnetic field is generated around the probe; and

FIG. 34 is an explanatory view showing the state where the swingingmagnetic field is combined around the probe.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

A first embodiment of the invention will be described referring to FIGS.1 to 28.

FIG. 1 is an explanatory view schematically showing the structure of acapsule endoscope control system of the embodiment.

A capsule endoscope control system (medical device control system) 1includes a capsule endoscope (insertion member, medical device) 3 to beinserted into a subject's body, a position detection sensor (directiondetection unit) 5 that detects information on the position or directionof the capsule endoscope 3, a triaxial Helmholtz coil (magnetic fieldgeneration portion) 7 that generates the magnetic field acting on thepermanent magnet installed in the capsule endoscope 3, a power source 9that supplies power to the triaxial Helmholts coil 7, an extracorporealdevice 11 that receives the image information transmitted from thecapsule endoscope 3, an operation unit 13 to which the controlinformation to the capsule endoscope 3 is input; a display unit 15 thatdisplays the image information transmitted from the capsule endoscope 3,and a control unit (user interface control unit) 17 that controls thetriaxial Helmholts coil 7, the operation unit 13, the display unit 15,and the like.

FIG. 2 is a schematic view of the structure of the capsule endoscopecontrol system 1 shown in FIG. 1.

The capsule endoscope control system 1 is provided with a user interface19 which includes the operating unit 13 to which the control informationinput by the operator to the capsule endoscope 3 is input, and thedisplay unit 15 that displays the image information acquired by thecapsule endoscope 3. The control unit 17 includes a magnetic fieldcontrol unit (magnetic field pattern storage portion, magnetic fieldpattern change portion, predetermined value change portion) 21 thatcontrols the direction of the magnetic field generated by the triaxialHelmholts coil 7 based on the input control information, and a displayinformation determination portion (user interface control unit) 25 thatdetermines the information displayed to the user interface 19.

The power source 9 that receives control signals from the control unit17 is disposed so as to supply power to the triaxial Helmholts coil 7based on the control signal.

The position detection sensor 5 detects the induced magnetism generatedfrom the capsule endoscope 3, and outputs the signal based on thedetected induced magnetism to the control unit 17. The extracorporealdevice 11 receives the image information obtained to be transmitted bythe capsule endoscope 3 to the outside, and outputs the received imageinformation to the control unit 17.

FIG. 3 is a block diagram of the capsule endoscope control system 1shown in FIG. 1.

Data with respect to the direction of the capsule endoscope 3 input fromthe position detection sensor 5 to the control unit 17, and the controldirection of the capsule endoscope 3 (to be described later) are inputto the display information determination portion 25. Then data to beoutput to the display unit 15 or the operation unit 13 are generatedbased on the discordance between the direction information and thecontrol information.

The user interface 19 receives the input of the operator so as todetermine the subsequent control direction.

The determined control direction is returned to the display informationdetermination portion 25, and input to the magnetic field control unit21. The direction of the capsule endoscope 3 is input to the magneticfield control unit 21 such that the power supply to be connected to thetriaxial Helmholtz coil 7 is controlled based on the discordance betweenthe control direction and the direction of the capsule endoscope 3.

FIG. 4 is a view showing selection of the magnetic field pattern shownin FIG. 3.

Referring to FIG. 4, a plurality of magnetic field patterns are storedin the magnetic field control unit 21. Based on the information input tothe magnetic field control unit 21, the predetermined magnetic fieldpattern is selected so as to be output.

FIG. 5 is a view schematically showing the capsule endoscope 3 and theextracorporeal device 11 shown in FIG. 1.

Referring to FIG. 5, the capsule endoscope 3 includes an exterior 27that contains various elements therein, an imaging portion 29 that takesthe image of the inner wall of the passage of the subject's body cavity,a battery 31 that drives the imaging portion 29, an induced magnetismgeneration portion 33 that generates the induced magnetism using theaforementioned triaxial Helmholtz coil 7, and a permanent magnet(magnetic field response portion) 3 as a driving magnet that drives thecapsule endoscope 3.

Instead of the permanent magnet 35, an electromagnet may be used as thedriving magnet but not limited thereto.

The exterior 27 is formed of a cylindrical capsule body with a rotatingaxis (insertion direction, center axis) R of the capsule endoscope 3 asthe center axis, a hemispherical top cover 37 that covers the leadingend of the body, and a hemispherical end that covers the rear end of thebody, thus constituting the liquid tight capsule container.

A helical portion (driving force generation portion) 39 formed as a wirematerial having a circular cross section is provided on the outerperipheral surface while being wound around the rotating axis R.

The helical portion 39 converts the rotation of the capsule endoscope 3around the rotating axis R into the driving force for forward andreverse movements. In the case where the passage of the cavity iscurved, for example, the external force is applied from the wall surfaceof the cavity of the internal organ. The external force directs thecapsule endoscope 3 toward the advancing direction, thus improving theautomatic inserting operation.

The imaging portion 29 is formed of a CCD (Charge Coupled Device) 47that acquires the image of the inner wall surface of the passage of thesubject's cavity, a lens that produces the image of the inner wallsurface of the passage of the subject's cavity on the CCD 47, an LED(Light Emitting Diode) 45 that illuminates the inner wall surface of thepassage of the cavity, a processing circuit 41, and a radio element 49that sends the image signal to the extracorporeal device 11.

The induced magnetism generation portion 33 includes at least a magneticinduced coil 51 that generates the induced magnetic field through themagnetic field generated by the triaxial Helmholtz coil 7. The magneticinduced coil 51 is disposed such that the center axis substantiallyaccords with the rotating axis R of the capsule endoscope 3. The innerperipheral surface of the magnetic induced coil 51 may be provided witha core member formed of, for example, ferrite. A resonance circuit thatcontains the magnetic induced coil 51 as the component may also beformed.

Referring to FIG. 5, the extracorporeal device 11 is formed of anantenna 53 that receives the image information transmitted from thecapsule endoscope 3, a processing circuit 55 that processes the receivedimage information, an input/output portion 57 that outputs the imageinformation that has been processed to the control unit 17, and acontrol circuit 59 that control the aforementioned components.

FIG. 6A is an explanatory view of the display on the display unit 15.FIG. 6B is an explanatory view on the display when the discordanceexceeds the boundary conditions (discordance amount, duration).

Referring to FIG. 6A, the display unit 15 displays an acquired imagedisplay 61, an absolute coordinate system display 63, a discordance overdisplay 67, and a time over display 67, respectively.

The acquired image display 61 serves to display the image informationthat has been taken by the imaging portion 29, on which a cross markindicating the center of the image and a control direction mark 69indicating the control direction of the magnetic field are superimposed.

In this way, the control direction is superimposed on the currentadvancing direction of the capsule endoscope 3. This allows the operatorwho inputs the control direction to identify the control stateintuitively. Accordingly, the operability of the capsule endoscope 3 maybe improved.

The absolute coordinate system display 63 has the current direction ofthe capsule endoscope 3 indicated by the solid line superimposed on thecontrol direction indicated by the broken line.

The discordance over display 65 illuminates when the amount ofdiscordance between the current direction of the capsule endoscope 3 andthe control direction exceeds the predetermined boundary condition asshown in FIG. 6B. Likewise, the time over display 67 illuminates whenthe time elapsed exceeds the predetermined duration in the state wherethe discordance amount exceeds the predetermined amount.

The display bar indicating the discordance and the boundary condition ofthe discordance may also be provided. The length of the illuminatingportion of the display bar changes in accordance with the discordance.

The amount of the discordance between the direction of the capsuleendoscope 3 and the control direction is displayed as described abovesuch that the operator who inputs the control direction may identify thecontrol state easily.

FIG. 7A is a view showing the concept of the display of the controldirection on the display unit 15. FIG. 7B is an explanatory view of thestate where the control direction is displayed on the acquired imagedisplay 61.

As shown in FIG. 7A, in the state where the control direction C deviatesfrom the direction of the rotating axis R as the advancing direction ofthe capsule endoscope 3, the control direction mark 69 is displayed atthe intersection P of the top cover 37 of the capsule endoscope 3 withthe control direction C on the acquired image display 61 (see FIG. 7B).

FIG. 8A is a schematic view of the operation unit 13 shown in FIG. 1.

The operation unit 13 includes a direction control lever 69 throughwhich the control information with respect to the direction of thecapsule endoscope 3 is input, a forward/reverse lever 71 through whichthe forward/reverse information is input, an accelerator 73 throughwhich the information of the speed upon forward/reverse movement, afeedback switching portion 75 that switches the process for switchingthe discordance information, and a magnetic field change patternswitching portion 77 for switching the pattern of the magnetic fieldgenerated by the triaxial Helmholtz coil 7.

The feedback switching portion 75 includes an automatic insertion modeswitch 79, a discordance information display switch 81, a directionfeedback switch 83, and a kinesthetic sense feedback switch 85.

The magnetic field change pattern switching portion 77 includes a normalmagnetic field switch 87, a maximum torque switch 89, and a jigglingswitch 91.

FIG. 8B is a schematic view of the structure of the direction controllever shown in FIG. 8A.

The direction control lever 69 includes a lever body (movable body) 93,and a support portion 95 that rotatably supports the lever body 93. Thesupport portion 95 is provided with a shaft 97 that rotatably supportsthe lever body 93 around the direction perpendicular to each portion.The support portion 95 includes a feedback portion 99 that is controlledby the control unit 17 based on the discordance information. Thefeedback portion (the discordance information transmission unit,oscillating body, reaction force generation unit, load generation unit)99 includes an encoder (not shown) that senses the inclined angle of thelever body 93, and a motor (not shown) that generates the reaction forcethat inclines the lever body 93 opposite to the inclination thereof.

The motor may be structured to generate the reaction force, or tooscillate the lever body 69. Alternatively, it may be structured toresist against the inclination of the lever body 93.

The use of the above-structured direction control lever 69 allows thefeedback portion 99 to transmit the discordance information to theoutside through oscillation. Alternatively, the discordance informationmay be transmitted to the outside as the load against the movement ofthe lever body 93.

FIG. 9A is an explanatory view of another exemplary structure of thedirection control lever shown in FIG. 8B. FIG. 9B is further exemplarystructure of the direction control lever shown in FIG. 8B.

The motor may be disposed as shown in FIG. 8B so as to oscillate thelever body 93. However, an eccentric motor (discordance informationtransmission portion, oscillating body) 101 may be disposed within thelever body 93 as shown in FIG. 9A, and rotated to oscillate the leverbody 93.

The use of the eccentric motor 101 may simplify the structure of thedirection control lever 69. The eccentric motor 101 is controlled basedon the discordance information so as to change the resonance frequencyand range of the resultant oscillation, thus transmitting thediscordance information to the operator. For example, the resonancefrequency may be increased as the discordance becomes large, andmeanwhile, the resonance frequency may be decreased as the discordancebecomes small such that the discordance information may be transmitted.

The motor may be disposed as shown in FIG. 8B so as to resist againstthe inclination of the lever body 93. Alternatively, the lever body 93may include a spherical body (discordance information transmittingportion, load generation portion) 103, and a friction portion(discordance information transmitting portion, load generation portion)105 that is urged against the spherical body 103 and a linear actuator107 that urges the friction portion 105 so as to generate the resistingforce using the friction between the friction portion 105 and thespherical boy 103. The spherical body 103 may contain an acceleratorsensor 109 such as a gyro therein to detect the inclination of the leverbody 93.

The suppressing force applied by the linear actuator 107 is controlledbased on the discordance information for the purpose of controlling thefriction force between the spherical body 103 and the friction portion105, thus transmitting the discordance information to the operator. Forexample, when the discordance becomes large, the load to the movement ofthe lever body 93 is increased. Meanwhile, when the discordance becomessmall, the load is decreased. This makes it possible to transmit thediscordance information. The operator is allowed to perform therealistic operation, thus improving the operability of the lever body93.

The direction control lever 93 may be formed through the easier processcompared to the case for generating the reaction force to the movementof the lever body 93.

FIG. 10A is an explanatory view of the control direction informationwith respect to the capsule endoscope 3 input through the directioncontrol lever 69. FIG. 10B is an explanatory view of the controldirection of the capsule endoscope 3 based on the control directioninformation input through the direction control lever 69.

The direction control lever 69 is operated in upward, downward, left andright directions defined to correspond to those directions (see FIG.10B) of the rotating axis R of the capsule endoscope 3 as shown in FIG.10A. When the lever body 93 is inclined at the angle α from the upwardto the left direction, the magnetic field is formed to induce thecapsule endoscope 3 to be inclined at the angle α from the upward to theleft direction.

The angle θ′ of the control direction of the capsule endoscope 3 shownin FIG. 10B is controlled based on the inclined angle θ of the leverbody 93 shown in FIG. 10A. If the incline angle θ becomes large, theangle θ′ becomes large accordingly such that the force for inducing thecapsule endoscope 3 to the direction at the angle α is increased.

The respective change patterns of the magnetic field formed by thetriaxial Helmholtz coil 7 will be described hereinafter.

FIG. 11A is an explanatory view of the revolving magnetic field formedaround the capsule endoscope 3 in the revolving magnetic field mode.

The revolving magnetic field mode (normal mode) shown in FIG. 11Aindicates the magnetic field change pattern used for controlling thenormal capsule endoscope 3, which corresponds to the normal field switch87 of the operation unit 13.

In the aforementioned mode, the magnetic field revolves in one directionon a revolving magnetic field plane MP. The capsule endoscope 3 isrotated around the rotating axis while holding its position to make therotating axis R perpendicular to the revolving magnetic field plane MP.When the capsule endoscope 3 moves straight, the control direction ofthe capsule endoscope 3 substantially accords with the direction of therotating axis R.

FIG. 11B is an explanatory view of the rotation of the capsule endoscope3 in the revolving magnetic field mode.

The capsule endoscope 3 is rotated by revolving the revolving magneticfield plane MP while turning the magnetic field in one direction. Whenthe revolving magnetic field plane MP is revolved, torque is generatedat the permanent magnet 35 installed in the capsule endoscope 3, whichcontinues acting until the rotating axis R of the capsule endoscope 3becomes perpendicular to the revolving magnetic field plane MP.

Specifically, the torque is not generated so long as the magnetizationdirection of the permanent magnet 35 is perpendicular to the revolvingplane (defined by the rotating axis R and the control direction C) ofthe capsule endoscope 3. When the magnetization is directed along therevolving plane, the maximum revolving torque is generated. While themagnetization direction is held as described above, the magnitude of thetorque changes like the sinusoidal wave.

The capsule endoscope 3 may be rotated around the rotating axis R byallowing the revolving magnetic field to act on the capsule endoscope 3.The thus driven capsule endoscope 3 may be controlled further stablycompared to the case that allows the magnetic field formed by combiningthe revolving magnetic field and oscillating magnetic field (describedlater), or the revolving magnetic field to act on the capsule endoscope3.

FIG. 12 is an explanatory view of the magnetic field generated aroundthe capsule endoscope 3 in the jiggling mode.

The jiggling mode shown in FIG. 12 has the magnetic field change patternthat swingably rotates the capsule endoscope 3, corresponding to thejiggling switch 91 of the operation unit 13. In this mode, the magneticfield is generated by combining the oscillating magnetic field foroscillating the intensity of the magnetic field and the revolvingmagnetic field that revolves in one direction on the revolving magneticfield plane MP which is in substantially the same direction as that ofthe rotating axis R of the capsule endoscope 3. The capsule endoscope 3rotates around the rotating axis R, and swings in both X and Ydirections shown in the drawing. The relationship between theoscillation cycle of the intensity of the magnetic field in theoscillating magnetic field and the revolving cycle of the revolvingmagnetic field may be controlled to regulate the direction of the swingmotion. Further, the rotating axis R is allowed to perform the swingmotion (precessional motion) that allows the rotating axis R to rotatearound the predetermined axis.

In the case where the capsule endoscope 3 is inserted to move forwardthrough the nearly closed passage of the cavity, for example, thecollapsed intestine, the capsule endoscope 3 is swingably rotated towiden the passage of the body cavity so as to further move forward.

FIG. 13 is an explanatory view of the magnetic field generated aroundthe capsule endoscope 3 in the maximum torque mode.

The maximum torque mode as shown in FIG. 13 indicates the magnetic fieldchange pattern mainly used for turning the rotating axis R of thecapsule endoscope 3, corresponding to the maximum torque switch 89 onthe operation portion 13.

The magnetic field in the aforementioned mode functions as the revolvingmagnetic field that revolves bidirectionally on the revolving magneticfield plane MP in the predetermined angular range with respect to theintersection line L of the revolving magnetic field plane MP with theturning plane (defined by the rotating axis R and the control directionC) of the capsule endoscope 3.

The permanent magnet 35 installed in the capsule endoscope 3 is turnedto rotate around the turning plane accompanied with the rotation of theturning magnetic field. This makes it possible to constantly generatethe torque that is approximate to the maximum turn torque.

FIG. 14 is an explanatory view of the magnetic field change pattern inthe maximum torque mode.

As described above, the revolving magnetic field represents the magneticfield that revolves in the predetermined angular range with the centerset to the intersection line L on the revolving magnetic field plane MP.Specifically, it may be represented by an X-axis magnetic field MX, anda Y-axis magnetic field MY as shown in FIG. 14. The axis of abscissasrepresents time, and axis of ordinate represents the magnitude of themagnetic field of the revolving magnetic field.

The X-axis magnetic field MX may be expressed as the function of, forexample, cos(α sin ωt), and Y-axis magnetic field MY may be expressed asthe function of, for example, sin(α cos ωt).

As the magnetic field acting on the capsule endoscope 3 functions as therevolving magnetic field where the angle defined by magnetic fielddirection and the intersection line L becomes equal to or smaller thanthe predetermined angle, the torque that directs the capsule endoscope 3toward the control direction C may be generated constantly. Upon changein the direction of the capsule endoscope 3, the torque that directs thecapsule endoscope 3 toward the control direction C is constantlygenerated, thus allowing efficient change in the direction.

The aforementioned mode including the normal mode, jiggling mode,maximum torque mode and the like may be switched through the input tothe normal magnetic field switch 87, the maximum torque switch 89, andthe jiggling switch 91, respectively.

When the capsule endoscope 3 is under induced control in the normalmode, the mode may be automatically switched based on the informationwith respect to the discordance between the rotating axis R and thecontrol direction C of the capsule endoscope 3. As the discordance valuebecomes large, the mode may be switched from the normal mode to themaximum torque mode, and further to the jiggling mode. The mode mayfurther be switched from the normal mode to the jiggling mode, andfurther to the maximum torque mode.

Likewise the jiggling mode and the maximum torque mode, the other modebesides those aforementioned may be used to improve the turningperformance. It is possible to switch the mode in accordance with thetime at which the discordance continuously occurs. For example, the modemay be switched when the state where the discordance in excess of thepredetermined value continues for a predetermined time or longer.

When the maximum torque mode is switched to the jiggling mode or viceversa, the normal mode is interposed between the maximum torque mode andthe jiggling mode.

When the magnetic field change pattern is switched, the magnetic fieldmay be changed intermittently. This may interfere with the stabilizedcontrol of the capsule endoscope 3. However, the mode switching isperformed via the highly stabilized normal mode (revolving magneticfield) so as to execute the control of the capsule endoscope 3 with highstability.

The respective control modes with respect to the capsule endoscope 3will be described.

Each of FIGS. 15 to 17 schematically shows the automatic insertion modeof the capsule endoscope 3.

Referring to FIGS. 15 to 17, the automatic insertion mode is performedwhen the discordance between the rotating axis R and the controldirection C of the capsule endoscope 3 exceeds the predetermined valueso as to accord the control direction C with the rotating axis R of thecapsule endoscope 3, which is the control process corresponding to theautomatic insertion mode switch 79 on the operation portion 13.

Specifically, in the automatic insertion mode, the capsule endoscope 3goes forward based on the input through the forward/reverse lever 71 andthe accelerator 73 while interrupting the input through the directioncontrol lever 69 of the operation portion 13 (see FIG. 8).

Referring to FIG. 15, in the case where the capsule endoscope 3 isinduced within the passage of the body cavity, for example, intestine,the rotating axis R of the capsule endoscope 3 accords with the controldirection C at the linear portion of the intestine I.

Referring to FIG. 16, when the capsule endoscope 3 reaches the curvedarea of the intestine I, the capsule endoscope 3 turns in contact withthe intestine wall surface. Then the discordance between the rotatingaxis R and the control direction C occurs.

When the discordance is increased to exceed the predetermined value, thecontrol direction C is changed to accord with the rotating axis R.

The mode switching operation to the automatic insertion mode may beperformed based on the input to the aforementioned automatic insertionmode switch 79 (see FIG. 8). Alternatively, the automatic control modemay be switched from the other control mode when the discordance betweenthe rotating axis R and the control direction C exceeds thepredetermined value.

When the discordance increases to reach the predetermined value, thecontrol direction C is changed to accord with the rotating axis R. Thismakes it possible to allow the capsule endoscope 3 to easily movethrough the passage of the body cavity along the wall surface thereof.

The control direction C may be adjusted to accord with the rotating axisR directly. Alternatively, the control direction C may be made accordedwith the rotating axis R after overshooting in consideration with theelasticity of the intestine wall.

The image acquired by the capsule endoscope 3 is processed such that theadvancing direction of the capsule endoscope 3 is extracted. The centerof the acquired image is determined as the current advancing directionof the capsule endoscope 3. The control direction may be regulated basedon the discordance between the target advancing direction and thecurrent advancing direction of the capsule endoscope 3.

The automatic insertion mode may be realized by generating the magneticfield where the direction obtained by adding the discordance to thecurrent advancing direction of the capsule endoscope is determined asthe control direction.

The discordance management control mode will be described.

FIG. 18A is an explanatory view showing an example of the discordancemanagement control mode.

Referring to FIG. 18A, in the discordance management control mode, thecontrol is executed based on the operation direction information inputthrough the operation control lever 69, and the information of thediscordance between the rotating axis R of the capsule endoscope 3 andthe control direction.

Specifically, in the case where the rotating axis R of the capsuleendoscope 3 fails to follow up with the operation direction information,the size of the discordance information becomes large as the size of theoperation direction information becomes large. In this case, however,when the discordance information reaches the predetermined thresholdvalue, the control direction information is fixed to the constant valuewhile interrupting the input of the operation direction information soas to prevent the discordance from exceeding the predetermined thresholdvalue.

The above control prevents the discordance between the rotating axis Rand the control direction from being excessively large. If thediscordance becomes excessively large, the operation controllability isconsiderably deteriorated, resulting in, for example, difficulty in therotation of the capsule endoscope 3 around the rotating axis R.Deterioration in the operation controllability of the capsule endoscope3 may be prevented by keeping the discordance from being excessivelylarge.

FIG. 18B is an explanatory view of another example of the discordancemanagement control mode.

Referring to FIG. 18A, the discordance management control may beexecuted when the discordance information exceeds the predeterminedthreshold value. Until then, the control is not executed. Referring toFIG. 18B, the discordance management control may be executedprogressively such that the discordance information gradually approachesthe predetermined threshold value.

Under the aforementioned control, the operation direction information isgradually interrupted rather than suddenly such that the operator isnotified that the discordance information has reached the predeterminedthreshold value.

Each of FIGS. 19A and 19B is an explanatory view of a further example ofthe discordance management control mode. FIG. 19A has an axis ofabscissas representing the operation direction information input throughthe direction control lever 69. FIG. 19B has an axis of abscissasrepresenting time.

Referring to FIGS. 19A and 19B, in the exemplary discordance managementcontrol mode, when the value of the discordance information reaches thesecond threshold value, the discordance management control is executedsuch that the value does not exceed the second threshold value. If thestate under the discordance management control continues for apredetermined period of time, the discordance management control isfurther executed such that the value does not exceed the first thresholdvalue. The first threshold value is smaller than the second thresholdvalue as shown in the drawing.

The discordance management control may be executed by controlling thecontrol direction while regulating the operation direction informationas described above. Alternatively, the control may be executed forchanging the change pattern of the magnetic field generated by thetriaxial Helmholtz coil 7 or the intensity of the generated magneticfield.

The magnetic field change pattern is changed based on the discordancefor the purpose of preventing deterioration in operability of thecapsule endoscope 3. More specifically, in the case where the magneticfield change pattern is no longer suitable for inducing the capsuleendoscope 3 to the control direction, and the discordance becomes toolarge, the magnetic field change pattern is changed to the one suitablefor inducing the capsule endoscope 3, or the intensity of the generatedmagnetic field is changed so as to prevent the increase in thediscordance.

The kinesthetic feedback control process will be described.

FIG. 20A is a view showing an example of the relationship between thediscordance information and the feedback information to the operationunit 13.

Referring to FIGS. 20A and 20B, the kinesthetic feedback control isexecuted for adjusting the level of the feedback of the discordanceinformation from the feedback portion 99 of the direction control lever69 based on the information with respect to the discordance between therotating axis R of the capsule endoscope 3 and the control direction.

More specifically, under the aforementioned control, the reaction forceto the lever body 93 is intensified proportional to the increase in thediscordance information, the amplitude of the oscillation transmitted tothe lever body 93 is increased, the oscillation cycle is reduced, or theresistance against the action of the lever body 93 is increased.

When the output of the feedback portion 99 reaches the upper limitvalue, the subsequent output from the feedback portion 99 is controlledto the constant value irrespective of the increase in the discordanceinformation. Thereafter, when the value of the discordance informationreaches the predetermined threshold value, the control direction isindependently controlled irrespective of the operation direction inputinformation as described with respect to the automatic insertion modesuch that the discordance information is prevented from exceeding thethreshold value. Alternatively, the control is executed to accord thecontrol direction with the rotating axis R.

The gradient of the ratio of the increase in the discordance informationto the level of the discordance information feedbacked from the feedbackportion 99 may be arbitrarily changed as dotted lines of FIG. 20A show.The sensitivity of the discordance information feedbacked from the leverbody 93 may be changed by adjusting the gradient. This makes it possibleto improve the sensitivity by, for example, making the gradient steep.

FIG. 20B is a view of another example of the relationship between thediscordance information and the feedback information to the operationportion 13.

As shown in FIG. 20A, the control is kept stopped until the output ofthe feedback portion 99 reaches the upper limit value. Alternatively, asshown in FIG. 20B, the control may be executed progressively such thatthe output of the feedback portion 99 gradually approaches the upperlimit value.

The aforementioned control allows the relatively small discordanceinformation to be feedbacked with the relatively large output from thefeedback portion 99. This makes it possible to prevent the capsuleendoscope 3 from being uncontrollable due to the increase in thediscordance. When the capsule endoscope 3 is brought into theuncontrollable state in the relatively wide passage of the body cavitylike stomach, it is likely to roll down therein. It is preferable toexecute the aforementioned control in such a case.

FIG. 21 is a view of another example of the relationship between thediscordance information and the feedback information to the operationunit 13.

Referring to FIG. 21, the control for functionally increasing the outputof the feedback portion 99 accompanied with the increase in thediscordance information may be executed by setting a neutral area Zwhere the discordance information is small and the signal is not outputfrom the feedback portion 99. When the discordance information valuereaches the predetermined threshold value, the control direction isindependently controlled irrespective of the input operation directioninformation as described with respect to the automatic insertion mode soas to prevent the discordance information from exceeding thepredetermined value. Alternatively the control may be executed to accordthe control direction with the rotating axis R.

While the discordance information is small, the output of the feedbackportion 99 is relatively small. Accordingly, a relatively large torquemay be easily applied to the capsule endoscope 3. That is, as thediscordance information feedbacked to the operator is at the low level,the operator is allowed to perform the input operation withoutconsidering the discordance information.

For example, the capsule endoscope 3 may be induced through the narrowpassage of the body cavity like the intestine while widening the wallsurface of the nearly closed passage. The large torque is required to beapplied to the capsule endoscope 3 to widen the nearly closed passage.For this, it is preferable to execute the aforementioned control.

The method for calculating the discordance of the capsule endoscope 3upon generation of the revolving magnetic field will be described.

Each of FIGS. 22A and 22B is an explanatory view of fluctuation in thetorque acting on the capsule endoscope 3. FIG. 22A is an explanatoryview of the positional relationship that maximizes the torque. FIG. 22Bis an explanatory view of the positional relationship that minimizes thetorque. FIG. 23 is a view of the relationship between the phase of themagnetic field direction and the intensity of the torque.

The permanent magnet 35 installed in the capsule endoscope 3 rotatesaccompanied with the revolving magnetic field as shown in FIGS. 22A and22B. The torque acting on the capsule endoscope 3 is maximized when themagnetic field direction accords with the one along the turning planedefined by the rotating axis R and the control direction C as shown inFIG. 22A. Meanwhile, it is minimized when the magnetic field directionis substantially perpendicular to the turning plane.

The intensity of the torque changes like a sinusoidal wave in the rangebetween the aforementioned maximum and minimum values as shown in FIG.23. The intensity changes based on the change in the rotating phase inthe direction of the revolving magnetic field.

The direction of the capsule endoscope 3 oscillates, that is,discordance occurs in accordance with the change in the intensity of thetorque.

In the case where the capsule endoscope 3 is turned toward the elasticwall surface while being in contact therewith, it is pressed to the wallsurface when the intensity of the torque becomes high. Meanwhile, thecapsule endoscope 3 is pushed back by the elastic wall surface when theintensity of the torque becomes low.

The discordance of the capsule endoscope 3 upon generation of therevolving magnetic field may be calculated based on the average value ofthe discordances obtained while the revolving magnetic field revolves byhalf. Alternatively, it may be calculated based on the discordance atthe maximum torque.

As the user interface is not influenced by the fluctuation of thediscordance owing to the oscillation of the torque, the operability mayfurther be stabilized.

In the aforementioned structure, the control unit 17 controls the userinterface 19 based on the discordance. This makes it possible totransmit the information with respect to the discordance to the operatorvia the user interface 19 (operation unit 13, display unit 15), thusimproving both the inducing stability and operability.

Specifically, the information with respect to the discordance istransmitted to the operator from the feedback portion 99. The feedbackof the information based on the discordance to the operator may beeasily performed, resulting in improved operability of the insertionmember.

As the information with respect to the discordance may be displayed onthe display unit 15, the discordance information may be transmitted tothe operator, thus improving the operability of the capsule endoscope 3.

The permanent magnet 35 may be fixed to the capsule endoscope 3 asdescribed above. Alternatively, it may be rotatably installed on thesame axis as the rotating axis R as shown in FIG. 24.

When the revolving magnetic field is caused to act on a capsuleendoscope 3A (insertion member, medical device), the permanent magnet 35rotates accompanied with the revolution of the revolving magnetic fieldindependently from the capsule endoscope 3A. When the direction of therevolving magnetic field plane is changed, the torque is generated atthe permanent magnet 35, and transmitted to the capsule endoscope 3A soas to be turned.

The capsule endoscope 3A and the permanent magnet 35 independentlyrotate around the rotating axis R without influencing other component ofthe capsule endoscope 3A. This makes it possible to reduce therotational period of the revolving magnetic field. This makes itpossible to reduce the fluctuation cycle of the generated torque in thesame way as the capsule endoscope 3.

In the case where the capsule endoscope 3A turns toward the elastic wallsurface like the intestinal wall while being in contact therewith, thecapsule endoscope 3A oscillates while being pressed against and pushedby the wall surface accompanied with the fluctuation of the torque. Inthis case, the fluctuation cycle of the torque is reduced to uniformizethe oscillation range, thus bringing the oscillation into convergence.

The capsule endoscope 3 may be formed independently from the externaldevice completely as described above. Alternatively, it may be connectedto the external device using a string member 111 at the rear end of acapsule endoscope (insertion member, medical device) 3B as shown in FIG.25. In this case, a bearing 113 is provided between the string member111 and the capsule endoscope 3B so as not to transfer the rotation ofthe capsule endoscope 3B to the string member 111.

The aforementioned structure allows the constant power supply to thecapsule endoscope 3B via the string member 111, and the transmission ofimage data taken by the imaging portion 29 to the outside via the stringmember 111. Accordingly, the power supply does not have to be installedinside, thus making the capsule endoscope 3B compact. As the image datado not have to be transmitted using radio wave, noise is not containedin the transmission data.

Referring to FIG. 26A, a probe may be formed by providing a stringmember 112 at the rear end of the capsule endoscope (insertion member)3B through which the rotating force is transmitted to the capsuleendoscope 3B, and a helical member 114 wound around the string member112. The aforementioned structure generates the driving force at thehelical member 114.

Another type of probe may further be formed by providing a motor 116 atthe end of the string member 112, and by arranging the permanent magnet35 and the capsule endoscope 35 so as to be relatively rotated. In theaforementioned structure, the revolving magnetic field is caused to actto regulate the direction of the capsule endoscope 3B. The motor 116 isoperated to rotate the probe to generate the driving force at thehelical portions 39 and 114.

Another type of probe may be formed by providing the permanent magnet 35with the magnetization direction substantially in parallel to therotating axis R of the capsule endoscope 3B as shown in FIG. 26C. In theaforementioned structure, parallel magnetic field is caused to act tocontrol the direction of the capsule endoscope 3B. The use of the motor116 rotates the probe entirely to generate the driving force at thehelical portions 39 and 114.

In the aforementioned case, the insertion member to be inserted into thesubject's body is formed as the capsule endoscope 3. However, theinsertion member is not limited to the capsule endoscope 3. It may beformed as the endoscope (insertion member, medical device) 3C as shownin FIGS. 27A and 27B.

Referring to FIGS. 27A and 27B, the endoscope 3C is rotatably providedwith a rotary member 115 which includes a helical member 39 and a magnet117.

In the aforementioned structure, when the revolving magnetic field actson the endoscope 3C, the magnet 117 drives to rotate the rotary member115 such that the helical member 39 provided therearound serves to movethe endoscope 3C forward and backward. Likewise the capsule endoscope 3,the direction of the revolving magnetic field plane is controlled toregulate the direction of the endoscope 3C.

The display unit 15 and the operation unit 13 may be formed as shown inFIGS. 6 and 8. A display unit 15′ and an operation unit 13′ may beformed as shown in FIG. 28A. The display unit 15′ includes an acquiredimage display 61, an entire coordinate system display 63, and anoperation display 119 of the operation unit 13′ to be described later.

The image information acquired by the imaging portion 29 is displayed onthe acquired image display 61, and a control direction mark 121indicating the direction of the magnetic field (control direction)formed by the triaxial Helmholtz coil 7 is superimposed thereon. Thecontrol direction mark 121 includes a cross mark as the center (controldirection) and the circle therearound.

The operation unit 13′ includes the operation display 119 that displaysthe operation information, and a mouse 123 through which the operationinformation is input. The operation display 119 displays a cursor 125that shows the current control direction.

Referring to FIG. 28B, the mouse 123 of the operation unit 13′ isoperated toward the operation direction of the capsule endoscope 3 whileclicking its right button for the purpose of inputting the operationdirection information of the capsule endoscope 3. Accordingly, therevolving magnetic field plane MP is controlled to regulate the controldirection C.

When the click of the mouse 123 is released, the cursor 125 returns tothe center such that the control direction C is controlled to accordwith the rotating axis R of the capsule endoscope 3, resulting instraight movement.

The speed of the forward/reverse movement of the capsule endoscope 3 maybe input using the wheel of the mouse, for example.

Second Embodiment

A second embodiment of the invention will be described referring toFIGS. 29 to 34.

The structure of a probe control system 201 according to the embodimentof the invention is basically the same as that of the capsule endoscopecontrol system according to the first embodiment except theconfiguration of the insertion member (probe) to be inserted into thesubject's body, and the process for detecting its position. In thepresent embodiment, the configuration of the probe, and the positiondetection unit thereof will only be described. The other explanationwith respect to the control and the like, thus, will be omitted.

FIG. 29 is an explanatory view schematically showing a structure of theprobe control system according to the embodiment.

The same components as those of the first embodiment are designated asthe same reference numerals, and explanations thereof, thus, will beomitted.

The probe control system (medical device control system) 201 includes aprobe (insertion member) 203 to be inserted into the subject's body, anX-ray apparatus (direction detector) 205 that detects the informationwith respect to the position or the direction of the probe 203, atriaxial Helmholtz coil 7 that generates the magnetic field acting onthe permanent magnet installed in the probe 203, a power supply 9 thatsupplies power to the triaxial Helmholtz coil 7, a feeder 211 that feedsthe probe 203, an operation unit 13 through which the controlinformation is input to the probe 203, a display unit 15 that displaysthe image information transmitted from the probe 203, and a control unit17 that controls the triaxial Helmholtz coil 7, the operation unit 13,and the display unit 15 and the like.

Referring to FIG. 30, the probe 203 contains a permanent magnet 235therein for controlling the direction of the probe 203. The permanentmagnet 235 is provided such that its magnetization direction accordswith the longitudinal axis of the probe 203.

The probe 203 may be used as the insertion member as described above, orthe capsule endoscope as described in the first embodiment. Referring toFIG. 31, it is preferable to provide the permanent magnet 35 installedin the capsule endoscope such that its magnetization direction accordswith the longitudinal axis of the capsule endoscope.

The X-ray apparatus 205 is formed of an image detection unit 205A thatdetects the position and direction information with respect to the probe203, and an X-ray image display unit 205B that displays the detectedimage information.

The control pattern of the probe 203 will be described.

FIG. 32 is an explanatory view of a magnetic field pattern that controlsthe direction of the probe 203 to the predetermined direction.

The direction of the probe 203 may be controlled to the predetermineddirection by forming a parallel magnetic field around the probe 203 asshown in FIG. 32 such that the direction of the parallel magnetic fieldaccords with the predetermined direction.

The probe 203 is fed by the feeder 211 while controlling the directionof the probe 203 so as to be induced to the predetermined site. Theoperator performs the inducing operation while confirming the positionand direction of the probe 203 displayed on the X-ray image display unit205B.

FIG. 33 is an explanatory view of a magnetic field pattern that controlsthe leading end of the probe 203 to swingably rotate.

Referring to FIG. 33, a conical magnetic field that conically revolvesis formed around the probe 203 such that the leading end of the probe203 is controlled to swingably rotate. The nearly closed passage of thebody cavity may be widened by the swingably rotating leading end of theprobe, thus easily inducing the probe 203.

As the probe 203 is turned to the predetermined direction whileswingably rotating the leading end, the narrow passage may be widened toturn the probe 203.

FIG. 34 is an explanatory view of the magnetic field pattern thatcontrols the leading end of the probe 203 to swingably rotate in onedirection.

Referring to FIG. 34, the oscillating magnetic field that swingablyoscillates on the predetermined plane is formed to control such that theleading end of the probe 203 is swingably rotated. For example, theleading end of the probe 203 is turned while being swingably oscillatedon the same plane as that of turning. This makes it possible to allowthe probe 203 to be easily turned even in the nearly closed passage ofthe cavity. The leading end of the probe 203 may be swingably oscillatedon the plane substantially perpendicular to the turning plane such thatthe probe is allowed to turn even through the nearly closed passage ofthe cavity.

Upon switching operation from the conical magnetic field to theoscillating magnetic field and vice versa, the parallel magnetic fieldis formed at the interval between the conical magnetic field and theoscillating magnetic field. The magnetic field is likely to be changedintermittently upon the switching operation, which may deteriorate thecontrol stability of the probe 203. However, the control stability ofthe probe 203 may be held by inserting the parallel magnetic field withthe highest control stability upon the switching operation, resulting inthe stabilized control of the probe 203.

The embodiment has been described with respect to the probe as theinsertion member to be inserted into the subject's body. However, theendoscope or catheter may be used as the insertion member. The insertionmember may be selected from the catheter and endoscope conforming toneeds of the diagnosis and treatment, thus allowing suitable medicaltreatment.

In the aforementioned structure, the probe 203 is directed toward themagnetization. The magnetic field generation means such as the triaxialHelmholtz coil 7 may be simply structured for controlling the directionof the probe 203. Accordingly, the direction of the probe 203 may beeasily controlled.

In the medical device control system, the use of the electromagnet orthe magnet may simplify the structure of the magnetic field responseportion.

In the medical device control system, the insertion member issubstantially cylindrical. The magnetic field response portion exhibitsthe magnetization direction perpendicular to the insertion direction,and is rotatably disposed around the center axis of the substantiallycylindrical insertion member.

According to the invention, the direction of the insertion member may beregulated by controlling the revolving plane of the revolving magneticfield while causing the revolving magnetic field to act on the insertionmember. That is, the predetermined axial position of the permanentmagnet or the electromagnet may be regulated by controlling therevolving plane of the revolving magnetic field. As the relativepositional relationship between the predetermined axis and the insertionmember is fixed, the direction of the insertion member may be regulatedby controlling the predetermined axial position.

In the medical device control system, the magnetic field responseportion exhibits the magnetization direction perpendicular to theinsertion direction, and is fixed to the insertion member.

According to the invention, the insertion member may be directed towardone direction by causing the magnetic field perpendicular to theinsertion direction to act on the magnetic field response portion.

In the medical device control system, the magnetic field responseportion exhibits the magnetization direction substantially in parallelto the insertion direction.

According to the invention, the insertion member may be directed towardone direction by causing the magnetic field substantially in parallel tothe insertion direction to act on the magnetic field response portion.

In the medical device control system, the insertion member may be formedas one of the catheter and the probe.

According to the invention, the insertion member may be selected fromthe catheter or probe in accordance with the use in the passage of thesubject's cavity for diagnosis or treatment, thus allowing appropriatemedical treatment.

In the medical device control system, the insertion member may be formedas one of the endoscope that acquires the image of the subject's bodycavity, and the capsule endoscope.

According to the invention, the insertion member may be selected fromthe endoscope or capsule endoscope in accordance with the use in thepassage of the subject's cavity for diagnosis or treatment, thusallowing appropriate medical treatment.

In the medical device control system, the user interface displays theacquired image of the subject's body cavity, as well as the insertiondirection of the endoscope or the capsule endoscope superimposedthereon.

According to the invention, the operator is allowed to identify theacquired image displayed on the acquired image display unit as well asthe direction information of the insertion member. This makes itpossible to acquire a large amount of information at a time, and toimprove the operability of the insertion member.

In the medical device control system, the driving force generationportion is formed of a rotary driving portion that rotates the insertionmember or the outer surface thereof at one end of the center axis of thesubstantially cylindrical insertion member, and a helical portionprovided on the outer surface of the insertion member around the centeraxis of the substantially cylindrical insertion member.

According to the invention, the revolving magnetic field is caused toact on the insertion member to rotate the insertion member around thecenter axis. The helical portion provided on the outer surface rotatesaccordingly to generate the driving force. This makes it possible toinduce the insertion member.

In the medical device control system, the insertion member is formed asthe substantially cylindrical capsule endoscope provided with thehelical portion on the outer surface of the capsule endoscope around thecenter axis thereof.

According to the invention, the revolving magnetic field is caused toact on the capsule endoscope to rotate around the center axis. Thehelical portion provided on the outer surface rotates accordingly togenerate the driving force. This makes it possible to induce theinsertion member. In the case where the passage of the body cavity iscurved, the external force is applied through the wall surface of thepassage of the internal organ such that the insertion member is directedtoward the penetrating direction, thus improving the automatic insertionoperation.

1. A medical device control system comprising: a medical deviceincluding an insertion member inserted into a subject's body, having itsdirection controlled by magnetism, and a magnetic field response portiondisposed within the insertion member for generating torque in responseto a magnetic field applied from outside the subject's body; a directiondetection unit that detects an insertion direction of the insertionmember; a user interface through which a control direction for theinsertion direction is input by an operator; a magnetic field generationportion that acts on the magnetic field response portion to generate amagnetic field for directing the insertion member to the controldirection; a magnetic field pattern storage portion that stores aplurality of magnetic field patterns generated by the magnetic fieldgeneration portion; and a magnetic field control unit that determinesthe control direction of the insertion member based on a detectionresult from the direction detection unit and an input result to the userinterface, selects a magnetic field pattern automatically from theplurality of magnetic field patterns based on a discordance between theinsertion direction and the control direction, and controls the magneticfield generation portion in accordance with the control direction andthe selected magnetic field pattern.
 2. The medical device controlsystem according to claim 1, wherein: the magnetic field responseportion comprises one of a magnet and an electromagnet that exhibits amagnetization direction substantially perpendicular to the insertiondirection; the magnetic field pattern storage portion stores a firstmagnetic field pattern that comprises a revolving magnetic field thatrevolves on a plane substantially perpendicular to the controldirection; the magnetic field pattern storage portion stores a secondmagnetic field pattern that comprises a magnetic field formed bycombining a revolving magnetic field that revolves on a planesubstantially perpendicular to the control direction and an oscillatingmagnetic field that oscillates substantially in parallel to the controldirection; and the magnetic field control unit selects the firstmagnetic field pattern when the discordance is equal to or smaller thana predetermined value, and selects the second magnetic field patternwhen the discordance is bigger than the predetermined value.
 3. Themedical device control system according to claim 1, wherein: themagnetic field response portion comprises one of a magnet and anelectromagnet that exhibits a magnetization direction substantiallyperpendicular to the insertion direction; the magnetic field patternstorage portion stores a first magnetic field pattern that comprises arevolving magnetic field that revolves on a plane substantiallyperpendicular to the control direction; the magnetic field patternstorage portion stores a second magnetic field pattern that comprises afluctuating magnetic field having its direction fluctuated on a planesubstantially perpendicular to the insertion direction, and having anangle formed by an intersection line of a plane substantiallyperpendicular to the control direction with a plane that contains theinsertion direction and the control direction, and the magnetic fielddirection of the fluctuating magnetic field varies within apredetermined range; and the magnetic field control unit selects thefirst magnetic field pattern when the discordance is equal to or smallerthan a predetermined value, and selects the second magnetic fieldpattern when the discordance is bigger than the predetermined value. 4.The medical device control system according to claim 3, wherein: anintensity of the fluctuating magnetic field is kept constant, and anangle formed by the direction of the fluctuating magnetic field, and theintersection line varies continuously within a predetermined range. 5.The medical device control system according to claim 1, wherein: themagnetic field response portion comprises one of a magnet and anelectromagnet that exhibits a magnetization direction substantially inparallel to the insertion direction; the magnetic field pattern storageportion stores a first magnetic field pattern that comprises a magneticfield substantially in parallel to the control direction; the magneticfield pattern storage portion stores a second magnetic field patternthat an oscillating magnetic field that oscillates around the controldirection and an angle formed by the oscillating magnetic field and thecontrol direction is within a predetermined range; and the magneticfield control unit selects the first magnetic field pattern when thediscordance is equal to or smaller than a predetermined value, andselects the second magnetic field pattern when the discordance is biggerthan the predetermined value.
 6. The medical device control systemaccording to claim 1, wherein: the magnetic field response portioncomprises one of a magnet and an electromagnet that exhibits amagnetization direction substantially in parallel to the insertiondirection; the magnetic field pattern storage portion stores a firstmagnetic field pattern that comprises the magnetic field substantiallyin parallel to the control direction; the magnetic field pattern storageportion stores a second magnetic field pattern that is formed bycombining the magnetic field substantially in parallel to the controldirection and a revolving magnetic field that revolves on a planesubstantially perpendicular to the insertion direction; and the magneticfield control unit selects the first magnetic field pattern when thediscordance is equal to or smaller than a predetermined value, andselects the second magnetic field pattern when the discordance is biggerthan the predetermined value.
 7. The medical device control systemaccording to claim 1, wherein: the magnetic field response portioncomprises one of a magnet and an electromagnet that exhibits amagnetization direction substantially in parallel to the insertiondirection; the magnetic field pattern storage portion stores a firstmagnetic field pattern that comprises the magnetic field substantiallyin parallel to the control direction; the magnetic field pattern storageportion stores a second magnetic field pattern that comprises afluctuating magnetic field having its direction fluctuated on a planethat contains the insertion direction and the control direction; and themagnetic field control unit selects the first magnetic field patternwhen the discordance is equal to or smaller than a predetermined value,and selects the second magnetic field pattern when the discordance isbigger than the predetermined value.
 8. The medical device controlsystem according to claim 1, wherein: the magnetic field responseportion comprises one of a magnet and an electromagnet that exhibits amagnetization direction substantially in parallel to the insertiondirection; the magnetic field pattern storage portion stores a firstmagnetic field pattern that comprises the magnetic field substantiallyin parallel to the control direction; the magnetic field pattern storageportion stores a second magnetic field pattern that comprises afluctuating magnetic field having its direction fluctuated on a planeperpendicular to a plane that contains the insertion direction and thecontrol direction; and the magnetic field control unit selects the firstmagnetic field pattern when the discordance is equal to or smaller thana predetermined value, and selects the second magnetic field patternwhen the discordance is bigger than the predetermined value.
 9. Themedical device control system according to claim 1, wherein: themagnetic field response portion comprises one of a magnet and anelectromagnet that exhibits a magnetization direction substantially inparallel to the insertion direction; the magnetic field pattern storageportion stores a first magnetic field pattern; the magnetic fieldpattern storage portion stores a second magnetic field pattern that anintensity of the magnetic field is bigger than that of the firstmagnetic field pattern; and the magnetic field control unit selects thefirst magnetic field pattern when the discordance is equal to or smallerthan a predetermined value, and selects the second magnetic fieldpattern when the discordance is bigger than the predetermined value. 10.A medical device control system comprising: a medical device includingan insertion member inserted into a subject's body, having its directioncontrolled by magnetism, and a magnetic field response portion disposedwithin the insertion member to generate torque in response to a magneticfield applied from outside the subject's body; an insertion forcegeneration portion that generates a driving force in an insertiondirection to the insertion member; a magnetic field generation portionthat acts on the magnetic field response portion to generate a magneticfield for directing the insertion member to a control direction; adirection detection unit that detects the insertion direction of theinsertion member; a user interface through which the control directionfor the insertion direction is input by an operator; a magnetic fieldcontrol unit that controls the insertion force generation portion andthe magnetic field generated by the magnetic field generation portionbased on a detection result from the direction detection unit and aninput result of a control direction to the user interface; wherein themagnetic field control unit carries out controls so that the insertionforce generation portion generates a driving force and has a controlmode that interrupts an input from the user interface, and controls themagnetic generation portion determined the control direction of theinsertion member from the control direction of the insertion member andthe direction of the insertion member detected by the directiondetection unit.
 11. A medical device control system according to claim10, wherein: the magnetic field control unit determines the controldirection of the insertion member such that a discordance between theinsertion direction and the control direction of the insertion member isequal to or smaller than a first predetermined value.
 12. The medicaldevice control system according to claim 10, wherein: the magnetic fieldcontrol unit includes the control mode performed when the discordancebetween the insertion direction and the control direction of theinsertion member exceeds a second predetermined value.
 13. The medicaldevice control system according to claim 11, wherein: the magnetic fieldcontrol unit is provided with a predetermined value change portion thatchanges the first predetermined value within an effective range.
 14. Themedical device control system according to claim 12, wherein: themagnetic field control unit is provided with a predetermined valuechange portion that changes the second predetermined value within aneffective range.